AZL-75773

alsa-lib versions 1.2.2 up to and including 1.2.15.2, prior to commit 5f7fe33, contain a heap-based buffer overflow in the topology mixer control decoder. The tplgdecodecontrolmixer1() function reads the numchannels field from untrusted .tplg data and uses it as a loop bound without validating it against the fixed-size channel array (SNDTPLGMAXCHAN). A crafted topology file with an excessive numchannels value can cause out-of-bounds heap writes, leading to a crash.